There goes the catalytic converter

[Petros]

the gasket between the head pipe and the exhaust manifold is likely bad. soak the two nuts on the exhaust head pipe flange with ATF or penetraiting oil over night (ATF works the best). Than jack the car up and put it on jack stands. use a breaker bar and a long exention (or several) and a 14 mm deep socket from under the car and back out the nuts. they usually come off, make sure the socket is seated all the way down on the flats of the nuts. I even ground the end of my deep socket off flat to allow more of the hex to engage the nut (most sockets have a tapered lead-in that make it easier to get it over the hex head, but it also reduces the contact with the flats).

The gasket only costs a few $. You will likely have to get the cat replaced or removed if you fix this leak, it may not run after you fix the gasket. Head pipes rare rust through because the exhaust gases are still hot and prevents corrosion. Further back where the exhaust is cooler moisture and combustion products precipitate out of the exhaust stream and cause the system to corrod away.

[irowiki]

ATF as in automatic transmission fluid? I did buy a can of PB Blaster last night, but the engine was hot so didn't put any on then.

Dad suggested going to Sears and buying some six point sockets, both normal and deep, to help get things off easier.

So your guess is the cat plugged which caused the gasket to go? Oddly the cat doesn't seem plugged now, or it isn't as plugged.

[dlb]

It would seem it is coming from the section of pipe in between the manifold and the cat. Any tips for getting those bolts off which hold the pipe to the manifold? Also for getting a new pipe, not sure this will be cheap

I'm starting to suspect maybe the cat got clogged, then the pipe north of it popped, and now the cat is clear enough to allow some passage.

you're right that it could be the head pipe but you might get lucky and have it just be the gasket between the manifold and head pipe. it's $3 so hope for that. when the engine is running, you should be able to see exhaust coming from wherever the leak is. sometimes using a flashlight helps.

the exhaust manifold has threaded studs on it. the head pipe is held in place by several 14 mm (usually) nuts. soak them for a few days with penetrating oil. i like PB blaster a lot, petros swears by ATF. whatever you use will do fine. even after a few days of soaking, i still had to use an electric impact gun with a butt load of extensions to reach those nuts and get them off. if they've been in place for many years, there will be a ton of corrosion built up on the threads so give them hell.

[irowiki]

Last night we had a bright work light and could see no leak when I stepped on the gas, I think ironically the old girl is running pretty clean

We were actually wondering how to smoke her up a bit, anything I can spray down the carb that would make some good smoke? (Seafoam? Carb cleaner?)

[dlb]

yes, seafoam can make a hell of a lot of smoke if you do it this way: get 2 cans of seafoam. position your car so the spark plugs are pointing away from anything you don't want to spray with toxic shit, ie house, other cars, kids, dogs, garden, groceries, etc. remove your spark plugs and pour seafoam in each cylinder until it starts to dribble out. this will use about 1.5 cans. let the car sit for 1-2 days. unplug the distributor (green electrical plug) so you don't accidentally ignite anything. with the spark plugs still out, crank the engine just a few times and spray the dirty seafoam all over your house, cars, kids, dog, etc. now put the spark plugs back in, plug the dizzy back in, and start the car. you will likely get about 5 minutes of white, grey, and black smoke. the white stuff is seafoam burning off, the black smoke is the carbon deposits, and the grey is a mix of the two. it's a good idea to rev the engine up a bit or drive it a little hard (yet safely and legally, of course) to clean all the crap out. i did this once and couldn't figure out why a car behind me went flying around like a bat out of hell. then i looked in my rear view mirror and saw that i was billowing out horrible clouds. he probably thought my car was blowing up and wanted to get away before he got caught in the blast. after 5 minutes or so of driving it all cleared up though.

[Petros]

pour some old ATF or Motor oil down the carb when it is reving. Even a lot of water spray will make a fair amount of steam out the exhaust.

best way to actually find an exhaust leak is to just run your hand around all the joints and places where it could be leaking, close enough to feel the hot exhaust spray. Do not touch any of the exhaust system, it could burn you.

[rer233]

[quote=

Dad suggested going to Sears and buying some six point sockets, both normal and deep, [/quote]


def 6 point sockets (i don't use 12 points- they round fasteners off.)

[Petros]

with the following sockets and open end wrenches there is nothing you can not remove from a Tercel: 8, 10, 12, 14, 17, 19. for sockets you will need both deep and normal depth. If you rebuild carbs you will also need a 9 mm deep socket in 1/4" drive to get one jet out. You will also need a 24 mm to get the trans and diff drain and filler plugs out. The only other socket is the large one on the axle nut, not sure I remember the size, 30 mm?

[rer233]

Yep- 30mm (or inch and 3/16.)

[irowiki]

After soaking, the nuts holding the pipe to the manifold came off effortlessly, almost too easy! The only thing resembling a gasket was a very hard ring (metal?) that had no gasket like properties. Is that it (photo below)

The U Clamps holding the cat on are still frozen solid, and I got the wrong deep end socket, so instead I just dropped the entire getup from the car. Will get the proper sockets, give them one more go, and cut them off if that doesn't work.

Instead of a test pipe, can I just knock whatever is left out of the cat and reinstall it?

[dlb]

yes, that's the gasket. it's hard to tell but it looks ok in that pic. i'd replace it when you put everything back together anyway. they're only a few dollars so that's cheap insurance.

[Petros]

that is the gasket alright, and if it is not all crumbling apart it can be reused. I reuse mine all the time, sometimes I put high temp gasket sealer on it to hold in place because they tend to get out of place before you can tighten down (this also helps seal it). It might have been leaking because the nuts were loose. this happens sometimes, and on the exhaust/intake manifold nuts and bolts because of the severe temp cycling. check the manifold bolts, should also be 14 mm. If the cat is not rusting through than yes, you can hog it out with a length of steel rebar or something similar.

Looks like that exhaust system was replaced, the factory one goes up over the top of the rear axle making impossible to get it out without cutting or separating the segments. going under the axle works except it makes the exhaust pipe vulnerable to damage (especially if you drive on rough roads with your handy 4x4 Tercel!).

BTW, the cheapest way to get some decent tools is to go to a pawn shop or 2nd hand store and just buy the sockets individually. they typically have full sets for big bucks, but also boxes of miscellaneous miss-matched sockets. Pick through them and get the socket sizes I listed above, and only buy the quality sockets (Craftman, proto, s-k, snap-on, etc.). If they have a big selection you can buy all you need, plus extensions and a u-joint, for less than $10. Or you can spend the big bucks and buy a set, half of the sockets you will never use (I have NEVER seen an 11 mm nut or bolt for example, but you always get them).

Yes, ATF is Automatic Transmission Fluid, the best penetrating oil EVER. I read about some tests on the various brands, and they found the AFT was way Superior. I got a rusted metal machinist adjustable protractor (uses set screw to adjust arms to various angles between two rulers) that I got in a free box at a garage sale. It was stuck solid, soaked for a week in WD-40 spraying every day, nothing, tried again with the more costly LPS-1, nothing. I set it in a can of used AFT, I pulled it out two days later and it moved without effort. I also once had one of those light struts that holds the corners of the front bumpers up on our tercels, they have a nut welded on to the ends and the 10mm bolt always rusts in place. The bolt had broken off when I removed them, and even after normal penetrating oil I could not unscrew the broken off bolt end with vise grips without risk of damage to the light metal strut. I also put it in the can of used AFT, and a few days later I could remove the rusted and broken off bolt by hand!!!

Here is the results that Machinery magazine found when removing very rusted 1" bolts from some industrial equipment, the nuts were soaked overnight in the various brands. Notice all reduced torque required to remove by over half, also that PB blaster did not perform so well compared to others. Kroil is very popular, and worked well, but it is just composed of a mix of crude (unrefined) oil and paint thinner. I use the AFT strait since it is a very thin oil, I have not tried thinning it further. the AFT mix resulted in a ten times reduction in the torque required, it is amazing stuff, and nothing else is worth using on really stuck stuff.

Penetrating oil ..... Average load

None ...................... 516 pounds
WD-40 ................... 238 pounds
PB Blaster .............. 214 pounds
Liquid Wrench ...... 127 pounds
Kano Kroil ............. 106 pounds
ATF-Acetone mix....53 pounds

[irowiki]

I don't think I have a rear axle?

Sears had a nice 11 piece six point metric normal socket set on sale so I got that, I'll see if I can find any second hand stores for the rest I need.

I need to find some sprayable ATF then!

As far as gutting the cat goes, would there be an issue with the exhaust going through a now empty chamber and getting any power loss, or will that not be an issue with our little engines anyway?

[dlb]

I don't think I have a rear axle?

haha, i caught that too.

I need to find some sprayable ATF then!

rather than sprayable ATF, i would just put some in an oiler can like this.

[irowiki]

Alright! Got everything back together using a section of flexible pipe for now. The cat was a bear to get off, the neighbor even came over and helped me wrestle with it!

Y'all will love this, I'm soaking the cat in PB Blaster and wondering why it doesn't seem to be doing much. Wife comes over "Why are you using the garage door lube on that?" (also made by PB blaster and in the same sort of can)

Car is louder but not wake the neighbors loud. Small bit of exhaust smell under the hood but nothing overwhelming like before. No more fumes in the car!